1. Technical Field
The present disclosure relates generally to the field of carcass processing, and particularly, is directed to an enhanced water disinfection process for use in the processing of a foodstuffs. More particularly, the disinfection process is designed as an intervention step in poultry processing to allow for continuous on-line processing of poultry carcasses that may have accidentally become contaminated during the evisceration process.
2. Background of the Related Art
The typical poultry processing plant receives live animals from the grow-out farms, slaughters the animals, drains the blood and then removes the feathers, xe2x80x9cpawsxe2x80x9d, heads and eviscera in the initial stages of processing. The carcasses are thereafter sent by way of mechanized line operations through a series of washing, chilling and sanitizing steps before the product is shipped as xe2x80x9cfreshxe2x80x9d product or packaged for freezing. These line operations typically consume large quantities of water.
Accordingly, the poultry processing industry has generally been characterized as a large volume consumer of water in conducting the slaughter, processing, and packing of the animals for both human consumption and other uses. Recent initiatives by the United States Department of Agriculture (USDA), under the jurisdiction of the Food Safety Inspection Service (FSIS), have resulted in a further increase in the volume of water used to wash poultry carcasses in order to meet the more stringent requirements of zero (0) tolerance for visible fecal contamination. Furthermore, recent introduction of Hazardous Analysis and Critical Control Point (HACCP) programs provide for the transition of the inspection process from one heavily weighted by USDA oversight to a more self-regulated format wherein the poultry producer shoulders more of the inspection burden. As a consequence, there has been additional heightened awareness and recognition of the need for greater product safety, including the reduction of microbial contamination levels.
The poultry industry has been actively seeking intervention methods designed to meet the current USDA regulations for continuous on-line processing. These regulations deal with the corrective actions that are mandated to remove carcasses that have been contaminated during evisceration with digestive tract materials. The regulations require that these contaminated carcasses be removed from the main processing line and transferred to an approved reprocessing line where the contamination can be removed by washing, trimming, vacuuming or a combination of these steps.
Prior method disinfection and processing goals have been to act as an intervention step which allows for the continuous on-line processing of poultry carcasses using a single point treatment which utilizes either trisodium phosphate washing or acidified chlorite. In general, single point treatment of a rapidly moving carcass on a production line is insufficient to meet the complex food safety requirements in a poultry processing plant. The single point treatment system using trisodium phosphate washing is described in U.S. Pat. No. 5,882,253. In the case of trisodium phosphate, the process is further disadvantaged by the introduction to the plant""s operations of increased levels of nutrients such as phosphates (i.e;, a byproduct of trisodium phosphate) that may need to be removed in the plant""s wastewater operations due to environmental discharge regulations or concerns.
Such environmental discharge regulations and concerns require that poultry processing plants decrease the level of nutrients such as phosphates in wastewater discharge. Additionally, the application of trisodium phosphate elevates the pH of the carcass being processed, as well as the process water all of which carries over to the plant""s chill system. The increased pH level in the chill system makes downstream chlorine disinfection less effective without significant chemical additions.
As discussed above and as dictated by the state of the art poultry or carcass processing plants, the current processes fail to appreciate the benefits associated with pH control, multiple point controlled treatment, or even the unexpected advantages to be gained by reducing the organic loads within such process water. By failing to appreciate these requirements, the conventional approaches commonly suffer from difficult treatment challenges and as a result, these approaches have been accompanied by disadvantageously high operating costs and reduced efficiency. This has in turn translated in to reduced product quality and reduced processing plant productivity.
The various objects and aspects of the present invention are met using an approach which focuses on appropriately regulating and controlling the pH of the process water to be disinfected and through addition, regulation and control of a disinfecting agent. The control of pH and level of disinfecting agent is implemented throughout multiple steps in the production process including any process water to be recovered and reused. This is in contrast to prior approaches which have failed to appreciate the benefits associated with pH control, multiple point controlled treatment, or even the unexpected advantages to be gained by reducing the organic loads within such process water.
Advantages of the present invention comprise processes which allow for the automated regulation of the pH of poultry processing water, preferably at certain stages of the process, so as to dramatically improve the efficiency and effectiveness of antimicrobial or other disinfection agents added. The poultry process treatment water which can especially benefit includes the water used in poultry scalding, picking, post-pick washing, evisceration, carcass washing and other stages of poultry processing designed to physically remove any fecal matter, ingesta and other digestive tract remnants from the slaughter and evisceration processes. Additionally, an improved device and method are provided for effecting economic and efficient regulation of disinfection agent and control of the disinfection chemistry throughout the multiple steps of the production process.
Physical removal of visible fecal material and other contaminants from poultry carcasses will be carried out by serial carcass washing steps (e.g., scalder, picker, post pick spray wash, inside/outside carcass washing cabinets and outside carcass washing cabinets) where medium pressure, high volume water spraying is employed. The introduction of USDA approved antimicrobial agents (e.g., calcium hypochlorite or others), applied at optimum pH control level for chlorine disinfection at multiple treatment stages (e.g., scalder, picker, post pick spray wash, inside/outside carcass wash and outside carcass wash) and using the best practical control methods is designed to significantly reduce microbial levels on all carcasses prior to and after their entry into the submersion chiller system.
The invention described herein is designed to employ the advantages of controlled chlorination (e.g., calcium hypochlorite and/or other USDA approved food grade biocides) at optimum pH levels, together with the proven effectiveness of increased contact time (CT) through the implementation of multiple stage treatment of the carcass during slaughter, evisceration, washing and chilling.
Additionally, an improved device and method are provided for effecting economic and efficient regulation of disinfection agent effectiveness comprising a system and method for removing a major portion of filterable materials including fats, oils and greases (FOG), total suspended solids (TSS), proteins, blood products, lipids and other materials represented as total is chemical oxidation demand (COD) from the chiller tank water.
The presently disclosed disinfection process for use in the processing of foodstuffs is designed as an intervention step in poultry processing to allow for continuous on-line processing of poultry carcasses that may have accidentally become contaminated during the evisceration process. Such on-line processing is designed to replace the need for off-line manual washing and cleaning of the contaminated carcasses. By eliminating such off-line manual washing, food safety will be enhanced due to the elimination of the physical handling of carcasses and the cross-contamination that may result from such physical handling. An additional benefit is that it will be possible to run the production process with a reduced number of interruptions, which will result in a more efficient production process. The disinfection process according to the present invention, include: the removal, using the processing plant""s existing washing, spraying and mechanical scrubbing devices (modified if required), of visible fecal material or other contaminants from the carcasses resulting from the mechanical evisceration process; the introduction of an enhanced antimicrobial treatment agent at multiple stages to improve food safety by reduction of total microbial levels; the improvement of disinfection in the facility""s overall production process including the carcass chiller system through the use of pH controlled chlorination to further reduce microbial counts, and the reduction of the amount of physical handling of carcasses and therefore, reduction of the potential for cross-contamination.
Further, the present invention is specifically designed to be easily incorporated into the processor""s existing production equipment and plant layout. This ease of implementation is accomplished by using, to the greatest extent possible, the processor""s existing carcass wash stations, scalders, pickers and other designated treatment points as the point of treatment by using the existing water piping and delivery systems as the means of delivery of the invention""s chemical and disinfection enhancements.
The invention described herein is designed to meet the current USDA regulations for removal of visible fecal material using the plant""s existing washing, spraying and mechanical scrubbing devices, and to reduce microorganism counts and improve food safety, all in a more cost effective and environmentally friendly manner than other approaches.
An additional benefit of the invention relates to those poultry processors who have or who intend to implement water reuse programs. Such water reuse programs, as is the subject of U.S. application Ser. No. 09/507,163, filed Feb. 18, 2000 and which is hereby incorporated by reference in its entirety, have met with favorable and advantageous results by returning reuse water that has been disinfected with ozone and then chlorinated at an advantageous dosage before being reintroduced to the production process at an upstream point, such as in the scalder or similar heating portion of the processing steps. The reintroduction of the chlorinated reuse water into the scalder or similar heating processing step causes a dramatic reduction in the levels of microorganisms associated with the carcasses that have not been found in the prior art. Also, it is an embodiment of the present disclosure, to introduce chlorinated and/or ozonated water (or other approved disinfectant) along the foodstuffs processing steps, particularly along the points where the use of heated water is applicable, such as in the scalder or similar processing steps which subject the carcasses to heated water. In such heated processing steps, the pores and tissue membranes of the carcasses are open and are more readily receiving of the surrounding water, i.e., the chlorinated and/or ozonated water, thereby having greater efficacy to the removal of microorganisms associated with such foodstuff processing.
In view of the foregoing, the advantages of the present disclosure include providing new methods for improving the effectiveness of the disinfection agent being used, new methods for improving the decontamination of poultry or other foodstuff and the water used in the processing of said poultry and other foodstuff, and water reuse methods which cause a reduction in the levels of microorganisms associated with the carcasses.